OBJECTIVE: To determine whether there was a difference between pre- and posthemodialysis serum albumin levels and, if so, whether that difference correlated with the amount of fluid removed during treatment. DESIGN: This descriptive study used a comparative data analysis strategy. SAMPLE/SETTING: 287 paired measurements of pre- and post-hemodialysis serum albumin levels were collected from 46 patients in a midwestern hemodialysis center. METHODS: Pre- and posthemodialysis serum albumin levels were obtained using the bromcresol green method. RESULTS: The pretreatment mean for serum albumin levels was 3.875 gm/dL (SD .4) and the posttreatment mean was 4.273 gm/dL (SD .599), significant at p < 0.0001. The amount of fluid removed during treatment was strongly correlated with the difference between pre- and posttreatment albumin levels (R = .6149; p < 0.0001). When data were sub-divided into three groups according to the amount of fluid removed during treatment, the mean differences between pre- and post hemodialysis albumin were significant at p < 0.0001. CONCLUSION: The strong correlation with fluid removed during hemodialysis suggests that fluid overload may be responsible for the significantly higher posttreatment albumin values in most patients.